Effectiveness of microdiscectomy for lumbar disc herniation: a randomized controlled trial with 2 years of follow-up.

STUDY DESIGN: Prospective randomized controlled trial.

OBJECTIVE: To assess effectiveness of microdiscectomy in lumbar disc herniation patients with 6 to 12 weeks of symptoms but no absolute indication for surgery.

SUMMARY OF BACKGROUND DATA: There is limited evidence in favor of discectomy for prolonged symptoms of lumbar disc herniation. However, only one randomized trial has directly compared discectomy with conservative treatment.

METHODS: Fifty-six patients (age range, 20-50 years) with a lumbar disc herniation, clinical findings of nerve root compression, and radicular pain lasting 6 to 12 weeks were randomized to microdiscectomy or conservative management. Fifty patients (89%) were available at the 2-year follow-up. Leg pain intensity was the primary outcome measure.

RESULTS: There were no clinically significant differences between the groups in leg or back pain intensity, subjective disability, or health-related quality of life over the 2-year follow-up, although discectomy seemed to be associated with a more rapid initial recovery. In a subgroup analysis, discectomy was superior to conservative treatment when the herniation was at L4-L5.

CONCLUSIONS: Lumbar microdiscectomy offered only modest short-term benefits in patients with sciatica due to disc extrusion or sequester. Spinal level of the herniation may be an important factor modifying effectiveness of surgery, but this hypothesis needs verification.